<?php // $Id: category_class.php,v 1.32.2.9 2008/11/27 11:50:20 tjhunt Exp $
/**
 * Class representing question categories
 *
 * @author Martin Dougiamas and many others. {@link http://moodle.org}
 * @license http://www.gnu.org/copyleft/gpl.html GNU Public License
 * @package questionbank
 */

// number of categories to display on page
define("QUESTION_PAGE_LENGTH", 25);

require_once("$CFG->libdir/listlib.php");
require_once("$CFG->dirroot/question/category_form.php");
require_once('move_form.php');

class question_category_list extends moodle_list {
	var $table = "question_categories";
	var $listitemclassname = 'question_category_list_item';
	/**
	 * @var reference to list displayed below this one.
	 */
	var $nextlist = null;
	/**
	 * @var reference to list displayed above this one.
	 */
	var $lastlist = null;

	var $context = null;

	function question_category_list($type='ul', $attributes='', $editable = false, $pageurl=null, $page = 0, $pageparamname = 'page', $itemsperpage = 20, $context = null){
		parent::moodle_list('ul', '', $editable, $pageurl, $page, 'cpage', $itemsperpage);
		$this->context = $context;
	}

	function get_records() {
		$this->records = get_categories_for_contexts($this->context->id, $this->sortby);
	}
	function process_actions($left, $right, $moveup, $movedown, $moveupcontext, $movedowncontext, $tocontext){
		global $CFG;
		//parent::procces_actions redirects after any action
		parent::process_actions($left, $right, $moveup, $movedown);
		if ($tocontext == $this->context->id){
			//only called on toplevel list
			if ($moveupcontext){
				$cattomove = $moveupcontext;
				$totop = 0;
			} elseif ($movedowncontext){
				$cattomove = $movedowncontext;
				$totop = 1;
			}
			$toparent = "0,{$this->context->id}";
			redirect($CFG->wwwroot.'/question/contextmove.php?'.
				$this->pageurl->get_query_string(compact('cattomove', 'totop', 'toparent')));
		}
	}
}

class question_category_list_item extends list_item {


	function set_icon_html($first, $last, &$lastitem){
		global $CFG;
		$category = $this->item;
		$this->icons['edit']= $this->image_icon(get_string('editthiscategory'),
				"{$CFG->wwwroot}/question/category.php?".$this->parentlist->pageurl->get_query_string(array('edit'=>$category->id)), 'edit');
		parent::set_icon_html($first, $last, $lastitem);
		$toplevel = ($this->parentlist->parentitem === null);//this is a top level item
		if (($this->parentlist->nextlist !== null) && $last && $toplevel && (count($this->parentlist->items)>1)){
			$this->icons['down'] = $this->image_icon(get_string('shareincontext', 'question', print_context_name($this->parentlist->nextlist->context)),
				$this->parentlist->pageurl->out_action(array('movedowncontext'=>$this->id, 'tocontext'=>$this->parentlist->nextlist->context->id)), 'down');
		}
		if (($this->parentlist->lastlist !== null) && $first && $toplevel && (count($this->parentlist->items)>1)){
			$this->icons['up'] = $this->image_icon(get_string('shareincontext', 'question', print_context_name($this->parentlist->lastlist->context)),
				 $this->parentlist->pageurl->out_action(array('moveupcontext'=>$this->id, 'tocontext'=>$this->parentlist->lastlist->context->id)), 'up');
		}
	}
	function item_html($extraargs = array()){
		global $CFG;
		$pixpath = $CFG->pixpath;
		$str = $extraargs['str'];
		$category = $this->item;

		$editqestions = get_string('editquestions', 'quiz');

		/// Each section adds html to be displayed as part of this list item
		$questionbankurl = "{$CFG->wwwroot}/question/edit.php?".
				$this->parentlist->pageurl->get_query_string(array('category'=>"$category->id,$category->contextid"));
		$catediturl = $this->parentlist->pageurl->out(false, array('edit'=>$this->id));
		$item = "<b><a title=\"{$str->edit}\" href=\"$catediturl\">".$category->name ."</a></b> <a title=\"$editqestions\" href=\"$questionbankurl\">".'('.$category->questioncount.')</a>';

		$item .= '&nbsp;'. $category->info;

		if (count($this->parentlist->records)!=1){ // don't allow delete if this is the last category in this context.
			$item .=  '<a title="' . $str->delete . '" href="'.$this->parentlist->pageurl->out_action(array('delete'=>$this->id)).'">
					<img src="' . $pixpath . '/t/delete.gif" class="iconsmall" alt="' .$str->delete. '" /></a>';
		}

		return $item;
	}

}


/**
 * Class representing question categories
 *
 * @package questionbank
 */
class question_category_object {

	var $str;
	var $pixpath;
	/**
	 * Nested lists to display categories.
	 *
	 * @var array
	 */
	var $editlists = array();
	var $newtable;
	var $tab;
	var $tabsize = 3;
//------------------------------------------------------
	/**
	 * @var moodle_url Object representing url for this page
	 */
	var $pageurl;
	/**
	 * @var question_category_edit_form Object representing form for adding / editing categories.
	 */
	var $catform;

	/**
	 * Constructor
	 *
	 * Gets necessary strings and sets relevant path information
	 */
	function question_category_object($page, $pageurl, $contexts, $currentcat, $defaultcategory, $todelete, $addcontexts) {
		global $CFG, $COURSE;

		$this->tab = str_repeat('&nbsp;', $this->tabsize);

		$this->str->course		 = get_string('course');
		$this->str->category	   = get_string('category', 'quiz');
		$this->str->categoryinfo   = get_string('categoryinfo', 'quiz');
		$this->str->questions	  = get_string('questions', 'quiz');
		$this->str->add			= get_string('add');
		$this->str->delete		 = get_string('delete');
		$this->str->moveup		 = get_string('moveup');
		$this->str->movedown	   = get_string('movedown');
		$this->str->edit		   = get_string('editthiscategory');
		$this->str->hide		   = get_string('hide');
		$this->str->publish		= get_string('publish', 'quiz');
		$this->str->order		  = get_string('order');
		$this->str->parent		 = get_string('parent', 'quiz');
		$this->str->add			= get_string('add');
		$this->str->action		 = get_string('action');
		$this->str->top			= get_string('top', 'quiz');
		$this->str->addcategory	= get_string('addcategory', 'quiz');
		$this->str->editcategory   = get_string('editcategory', 'quiz');
		$this->str->cancel		 = get_string('cancel');
		$this->str->editcategories = get_string('editcategories', 'quiz');
		$this->str->page		   = get_string('page');
		$this->pixpath = $CFG->pixpath;

		$this->pageurl = $pageurl;

		$this->initialize($page, $contexts, $currentcat, $defaultcategory, $todelete, $addcontexts);

	}



	/**
	 * Initializes this classes general category-related variables
	 */
	function initialize($page, $contexts, $currentcat, $defaultcategory, $todelete, $addcontexts) {
		$lastlist = null;
		foreach ($contexts as $context){
			$this->editlists[$context->id] = new question_category_list('ul', '', true, $this->pageurl, $page, 'cpage', QUESTION_PAGE_LENGTH, $context);
			$this->editlists[$context->id]->lastlist =& $lastlist;
			if ($lastlist!== null){
				$lastlist->nextlist =& $this->editlists[$context->id];
			}
			$lastlist =& $this->editlists[$context->id];
		}

		$count = 1;
		$paged = false;
		foreach ($this->editlists as $key => $list){
			list($paged, $count) = $this->editlists[$key]->list_from_records($paged, $count);
		}
		$this->catform = new question_category_edit_form($this->pageurl, compact('contexts', 'currentcat'));
		if (!$currentcat){
			$this->catform->set_data(array('parent'=>$defaultcategory));
		}
	}
	/**
	 * Displays the user interface
	 *
	 */
	function display_user_interface() {

		/// Interface for editing existing categories
		$this->output_edit_lists();


		echo '<br />';
		/// Interface for adding a new category:
		$this->output_new_table();
		echo '<br />';

	}

	/**
	 * Outputs a table to allow entry of a new category
	 */
	function output_new_table() {
		$this->catform->display();
	}


	/**
	 * Outputs a list to allow editing/rearranging of existing categories
	 *
	 * $this->initialize() must have already been called
	 *
	 */
	function output_edit_lists() {
		print_heading_with_help(get_string('editcategories', 'quiz'), 'categories', 'question');
		foreach ($this->editlists as $context => $list){
			$listhtml = $list->to_html(0, array('str'=>$this->str));
			if ($listhtml){
				print_box_start('boxwidthwide boxaligncenter generalbox questioncategories contextlevel' . $list->context->contextlevel);
				print_heading(get_string('questioncatsfor', 'question', print_context_name(get_context_instance_by_id($context))), '', 3);
				echo $listhtml;
				print_box_end();
			}
		}
		echo $list->display_page_numbers();
	 }



	/**
	 * gets all the courseids for the given categories
	 *
	 * @param array categories contains category objects in  a tree representation
	 * @return array courseids flat array in form categoryid=>courseid
	 */
	function get_course_ids($categories) {
		$courseids = array();
		foreach ($categories as $key=>$cat) {
			$courseids[$key] = $cat->course;
			if (!empty($cat->children)) {
				$courseids = array_merge($courseids, $this->get_course_ids($cat->children));
			}
		}
		return $courseids;
	}



	function edit_single_category($categoryid) {
	/// Interface for adding a new category
		global $COURSE;
		/// Interface for editing existing categories
		if ($category = get_record("question_categories", "id", $categoryid)) {

			$category->parent = "$category->parent,$category->contextid";
			$category->submitbutton = get_string('savechanges');
			$category->categoryheader = $this->str->edit;
			$this->catform->set_data($category);
			$this->catform->display();
		} else {
			error("Category $categoryid not found");
		}
	}


	/**
	 * Sets the viable parents
	 *
	 *  Viable parents are any except for the category itself, or any of it's descendants
	 *  The parentstrings parameter is passed by reference and changed by this function.
	 *
	 * @param	array parentstrings a list of parentstrings
	 * @param   object category
	 */
	function set_viable_parents(&$parentstrings, $category) {

		unset($parentstrings[$category->id]);
		if (isset($category->children)) {
			foreach ($category->children as $child) {
				$this->set_viable_parents($parentstrings, $child);
			}
		}
	}

	/**
	 * Gets question categories
	 *
	 * @param	int parent - if given, restrict records to those with this parent id.
	 * @param	string sort - [[sortfield [,sortfield]] {ASC|DESC}]
	 * @return   array categories
	 */
	function get_question_categories($parent=null, $sort="sortorder ASC") {
		global $COURSE;
		if (is_null($parent)) {
			$categories = get_records('question_categories', 'course', "{$COURSE->id}", $sort);
		} else {
			$select = "parent = '$parent' AND course = '{$COURSE->id}'";
			$categories = get_records_select('question_categories', $select, $sort);
		}
		return $categories;
	}

	/**
	 * Deletes an existing question category
	 *
	 * @param int deletecat  id of category to delete
	 */
	function delete_category($categoryid) {
		global $CFG;
		question_can_delete_cat($categoryid);
		if (!$category = get_record("question_categories", "id", $categoryid)) {  // security
			error("No such category $cat!", $this->pageurl->out());
		}
		/// Send the children categories to live with their grandparent
		if (!set_field("question_categories", "parent", $category->parent, "parent", $category->id)) {
			error("Could not update a child category!", $this->pageurl->out());
		}

		/// Finally delete the category itself
		delete_records("question_categories", "id", $category->id);
	}
	function move_questions_and_delete_category($oldcat, $newcat){
		question_can_delete_cat($oldcat);
		$this->move_questions($oldcat, $newcat);
		$this->delete_category($oldcat);
	}

	function display_move_form($questionsincategory, $category){
		$vars = new stdClass;
		$vars->name = $category->name;
		$vars->count = $questionsincategory;
		print_simple_box(get_string("categorymove", "quiz", $vars), "center");
		$this->moveform->display();
	}

	function move_questions($oldcat, $newcat){
		$questionids = get_records_select_menu('question', "category = $oldcat AND (parent = 0 OR parent = id)", '', 'id,1');
		if (!question_move_questions_to_category(implode(',', array_keys($questionids)), $newcat)) {
			print_error('errormovingquestions', 'question', $returnurl, $ids);
		}
	}

	/**
	 * Creates a new category with given params
	 *
	 */
	function add_category($newparent, $newcategory, $newinfo) {
		if (empty($newcategory)) {
			print_error('categorynamecantbeblank', 'quiz');
		}
		list($parentid, $contextid) = explode(',', $newparent);
		//moodle_form makes sure select element output is legal no need for further cleaning
		require_capability('moodle/question:managecategory', get_context_instance_by_id($contextid));

		if ($parentid) {
			if(!(get_field('question_categories', 'contextid', 'id', $parentid) == $contextid)) {
				error("Could not insert the new question category '$newcategory' illegal contextid '$contextid'.");
			}
		}

		$cat = new object();
		$cat->parent = $parentid;
		$cat->contextid = $contextid;
		$cat->name = $newcategory;
		$cat->info = $newinfo;
		$cat->sortorder = 999;
		$cat->stamp = make_unique_id_code();
		if (!insert_record("question_categories", $cat)) {
			error("Could not insert the new question category '$newcategory'");
		} else {
			redirect($this->pageurl->out());//always redirect after successful action
		}
	}

	/**
	 * Updates an existing category with given params
	 */
	function update_category($updateid, $newparent, $newname, $newinfo) {
		global $CFG, $QTYPES;
		if (empty($newname)) {
			print_error('categorynamecantbeblank', 'quiz');
		}

		// Get the record we are updating.
		$oldcat = get_record('question_categories', 'id', $updateid);
		$lastcategoryinthiscontext = question_is_only_toplevel_category_in_context($updateid);

		if (!empty($newparent) && !$lastcategoryinthiscontext) {
			list($parentid, $tocontextid) = explode(',', $newparent);
		} else {
			$parentid = $oldcat->parent;
			$tocontextid = $oldcat->contextid;
		}

		// Check permissions.
		$fromcontext = get_context_instance_by_id($oldcat->contextid);
		require_capability('moodle/question:managecategory', $fromcontext);

		// If moving to another context, check permissions some more.
		if ($oldcat->contextid != $tocontextid){
			$tocontext = get_context_instance_by_id($tocontextid);
			require_capability('moodle/question:managecategory', $tocontext);
		}

		// Update the category record.
		$cat = NULL;
		$cat->id = $updateid;
		$cat->name = $newname;
		$cat->info = $newinfo;
		$cat->parent = $parentid;
		// We don't change $cat->contextid here, if necessary we redirect to contextmove.php later.
		if (!update_record("question_categories", $cat)) {
			error("Could not update the category '$newname'", $this->pageurl->out());
		}

		// If the category name has changed, rename any random questions in that category.
		if (addslashes($oldcat->name) != $cat->name) {
			$randomqname = $QTYPES[RANDOM]->question_name($cat);
			set_field('question', 'name', addslashes($randomqname), 'category', $cat->id, 'qtype', RANDOM);
			// Ignore errors here. It is not a big deal if the questions are not renamed.
		}

		// Then redirect to an appropriate place.
		if ($oldcat->contextid == $tocontextid) { // not moving contexts
			redirect($this->pageurl->out());
		} else {
			redirect($CFG->wwwroot.'/question/contextmove.php?' .
					$this->pageurl->get_query_string(array(
					'cattomove' => $updateid, 'toparent'=>$newparent)));
		}
	}

	function move_question_from_cat_confirm($fromcat, $fromcourse, $tocat=null, $question=null){
		global $QTYPES;
		if (!$question){
			$questions[] = $question;
		} else {
			$questions = get_records('question', 'category', $tocat->id);
		}
		$urls = array();
		foreach ($questions as $question){
			$urls = array_merge($urls, $QTYPES[$question->qtype]->find_file_links_in_question($question));
		}
		if ($fromcourse){
			$append = 'tocourse';
		} else {
			$append = 'tosite';
		}
		if ($tocat){
			echo '<p>'.get_string('needtomovethesefilesincat','question').'</p>';
		} else {
			echo '<p>'.get_string('needtomovethesefilesinquestion','question').'</p>';
		}
	}




}

?>
